1. Technical Field
The present invention relates to cellular communication networks having the option to send short messages. It also relates to a method to deliver communication attempts in accordance with the determined attainability of a mobile terminal device. The present invention relates to a method to deliver communication attempts to mobile terminal devices with a minimized use of wireless connections. The invention further relates to a mechanism inside a Short Message Service Center (SMSC) to provide notifications for calling applications or network devices for informing them if mobile devices are reachable or not, and if they are reachable via General Packet Radio Service (GPRS) or Global System for Mobile communication (GSM).
2. Discussion of Related Art
Currently, in order to find out if a mobile terminal device is attainable, an application can send a Short Message (SM) to a handset and based on the result of the delivery of this SM the application knows if the handset is reachable or not. This implies also that the SM is actually delivered if the phone is reachable. Examples of this are push-type services which would benefit by not pushing to many subscribers when these are not reachable. E.g. a football score application would at the start of the match ‘poll’ all one hundred thousand fans and reduce the list down to just twelve thousand subscribers currently reachable. During the match, the amount of data pushed will be reduced dramatically and the resources used (without charging for it) is minimized.
Sometimes it would be desirable to know the reachability status without disturbing the terminal device. Presently, the SMs are sent anyway. There are some ways in the European Telecommunication Standard Institute (ETSI) specifications to send an SMS which the phone ‘may discard’ but it is not clear if all phones will comply with this procedure or not. In this case the air-interface capacity is used if the phone is reachable. In practice most applications just send all the stuff to all handsets and the SMSC capacity is wasted, and many more paging attempts are accordingly made as a result.
The standard procedures for delivering SMs can be found in the ETSI specifications for GSM and in the 3rd Generation Partnership Project (3GPP) specifications for the Short Message Service (SMS).
The main drawback of this standard procedure is that the mobile user has to get rid of these SMs pushed to him just to find out the status of the terminal device.